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Ike666 · September 18, 2011, 10:25 AM

I'm using some Lapua brass in my Remmy 700 PSS (.308), and I neck size the brass. It is on it's third cycle, so probably has quite a bit of case life left.

After following this discussion with great interest I decided to check it out in the lab (loading room). Using an RCBS case micrometer to check case length to the datum, I first ran it on a set of Forster chamber gauges.

GO: 0.000
NOGO: 0.004
FIELD: 0.0075

Then I checked the neck-sized brass, first in a Dillon headspace/case length gauge: all well within limits. Then I took a random 20% selection (10 cases) of the brass I had re-sized and checked them in the RCBS micrometer. The average (actually all except 1) gauged at 0.004 (same as NOGO chamber gauge).

Now, I knew the chamber in the Remington was getting long in the tooth, but it still checks within sammy [sic] specs. To seat a bullet 0.018 off the lands I'd have a COL of more that 3 inches. However, the rifle is still an absolute tack driver that will print .5 MOA groups as long as I do my part.

I also ran the case necks on the run-out gauge and the highest run-out was less than 0.001. The neck sizing was done on a Lee Collet die, and I've had really good experiences with it.

I'm not sure what all this means, except I'm going to have to watch the chamber/barrel on the Remmy.

September 18, 2011, 10:25 AM	#27
Ike666 Senior Member Join Date: October 10, 2009 Location: SW VA Posts: 491	I'm using some Lapua brass in my Remmy 700 PSS (.308), and I neck size the brass. It is on it's third cycle, so probably has quite a bit of case life left. After following this discussion with great interest I decided to check it out in the lab (loading room). Using an RCBS case micrometer to check case length to the datum, I first ran it on a set of Forster chamber gauges. GO: 0.000 NOGO: 0.004 FIELD: 0.0075 Then I checked the neck-sized brass, first in a Dillon headspace/case length gauge: all well within limits. Then I took a random 20% selection (10 cases) of the brass I had re-sized and checked them in the RCBS micrometer. The average (actually all except 1) gauged at 0.004 (same as NOGO chamber gauge). Now, I knew the chamber in the Remington was getting long in the tooth, but it still checks within sammy [sic] specs. To seat a bullet 0.018 off the lands I'd have a COL of more that 3 inches. However, the rifle is still an absolute tack driver that will print .5 MOA groups as long as I do my part. I also ran the case necks on the run-out gauge and the highest run-out was less than 0.001. The neck sizing was done on a Lee Collet die, and I've had really good experiences with it. I'm not sure what all this means, except I'm going to have to watch the chamber/barrel on the Remmy. __________________ ___________________ "I'm your huckleberry."